package day09;

import java.util.Scanner;

/**
 * @author tongchen
 * @create 2023-03-14 20:34
 */
public class Main {
  static   int count=0;//定义计数器
    public static void main(String[] args) {

        //定义输入
        Scanner scanner=new Scanner(System.in);
        int n=scanner.nextInt();
        int m=scanner.nextInt();
        int[][]arr=new int[m][n];
        went(arr, 0, 0);
        System.out.println(count);
    }
    public static void went(int[][]arr,int width,int height){
        //定义出口
        if(width>=arr[0].length||height>= arr.length){
            return ;
        }
        if(width==arr[0].length-1&&height== arr.length){
            count++;
            return;
        }
        went(arr, width+1, height);
        went(arr, width, height+1);
    }
}
